Response of white clover and grass to applications of potassium and nitrogen on a potassium-deficient hill soil

1988 ◽  
Vol 110 (1) ◽  
pp. 159-167 ◽  
Author(s):  
D. Simpson ◽  
D. Wilman ◽  
W. A. Adams

SummaryAll combinations of four levels of potassium and two of nitrogen were applied in each of 2 years to a hill sward on a brown podzolic soil with an 8 cm peaty surface horizon anda very low level of extractable K. The sward had been surface-sown 11 years before with white clover (Trifolium repens L.) and perennial ryegrass (Lolium perenne L.). During the course of the experiment, harvesting was by cutting, with an average interval between cuts of 5 weeks. The previous management had been sheep grazing.The proportion of clover in harvested herbage was increased by applied K and reduced by applied N. The clover grew strongly in the 1st year of cutting management where K, but no N, was applied, but there was much less clover in the 2nd year on all plots. The concentration of K in both clover and grass was greatly increased by applied K, but only the clover responded strongly in terms of extra herbage produced. This suggests that grass growth was N-limited, whereas the clover had sufficient N from symbiotic fixation.Applied K increased the size and weight of clover leaves, the rate of extension of the stolon main axis, and the number and length of stolon branches, but did not affect the rate of emergence of leaves on the stolon main axis. Applied N had a generally negative effect on the aspects of clover growth and morphology which were measured. The length and weight per ryegrass leaf blade were generally slightly increased by both applied K and applied N.

1984 ◽  
Vol 103 (1) ◽  
pp. 201-211 ◽  
Author(s):  
D. Wilman ◽  
P. Joy Pearse

SummaryEffects of three levels of N application and four intervals between harvests on field swards of perennial ryegrass (Lolium perenne L.) were studied during 6-week periods in summer and spring. Ryegrass was compared with tall fescue (Festuca arundinacea Schreb.) in spring and autumn.An increase in the interval between harvests from 1 to 6 weeks allowed a larger, positive response to applied N to develop in respect of dry-matter yield, weight per tiller, and leaf blade and sheath length. Response to N was expressed more in terms of larger leaf blades than in a larger number of tillers. Tall fescue leaf blade size was increased more than that of ryegrass by a period of uninterrupted growth in May.Within 1 week of its application, N had increased the N content of both emerging and dying leaf blades and had increased the width and reduced the weight per unit area of the emerging blades. The positive effect of N on blade width (and on blade length where uninterrupted growth was allowed) and its negative effect on weight per unit area were ‘carried through’ the sward, to be recorded a second time when that generation of blades had become the dying blades.Applied N increased the number of tillers, the rate of emergence of new tillers, the proportion of tiller buds which developed into tillers, and the proportion of relatively young tiller buds which developed.


Author(s):  
B.R. Watkin

AN Aberystwyth selection of tall fescue (Festuca arundinacea Schreb.), known as S170, was sown with certified New Zealand white clover (Trifolium repens) and re' clover (T. pratense) and compared under sheep grazing with other grass/clover pastures at the Grasslands Division Regional Station at Lincoln (Watkin, 1975) .


2020 ◽  
Vol 100 (1) ◽  
pp. 11-25 ◽  
Author(s):  
Guoyong Yan ◽  
Xiongde Dong ◽  
Binbin Huang ◽  
Honglin Wang ◽  
Ziming Hong ◽  
...  

We conducted a field experiment with four levels of simulated nitrogen (N) deposition (0, 2.5, 5, and 7.5 g N m−2 yr−1, respectively) to investigate the response of litter decomposition of Pinus koraiensis (PK), Tilia amurensis (TA), and their mixture to N deposition during winter and growing seasons. Results showed that N addition significantly increased the mass loss of PK litter and significantly decreased the mass loss of TA litter throughout the 2 yr decomposition processes, which indicated that the different responses in the decomposition of different litters to N addition can be species specific, potentially attributed to different litter chemistry. The faster decomposition of PK litter with N addition occurred mainly in the winter, whereas the slower decomposition of TA litter with N addition occurred during the growing season. Moreover, N addition had a positive effect on the release of phosphorus, magnesium, and manganese for PK litter and had a negative effect on the release of carbon, iron, and lignin for TA litter. Decomposition and nutrient release from mixed litter with N addition showed a non-additive effect. The mass loss from litter in the first winter and over the entire study correlated positively with the initial concentration of cellulose, lignin, and certain nutrients in the litter, demonstrating the potential influence of different tissue chemistries.


2021 ◽  
Vol 72 (11) ◽  
pp. 926
Author(s):  
M. Z. Z. Jahufer ◽  
J. L. Ford ◽  
G. R. Cousins ◽  
D. R. Woodfield

Assessment of the relative performance of white clover (Trifolium repens L.) cultivars, using multi-year and multi-location seasonal growth trials, is key to identification of material with specific and broad adaptation. This paper is based on a multi-year and multi-location study of 56 white clover entries comprising 14 commercial cultivars and 42 experimental synthetic lines evaluated for seasonal growth under rotational grazing across four locations in New Zealand over 4years. The four locations (and animals grazing) were: Kerikeri (beef cattle), Aorangi (beef cattle), Ruakura (dairy cattle), Lincoln (sheep). Significant (P<0.05) genotypic variation among the 56 entries, and genotype × year, genotype× location and genotype× season interactions, were estimated. We were able to identify cultivars and experimental synthetics with specific and broad adaptation to the three grazing management types. Cvv. AberDance, Apex, Demand, Prestige, Quartz and Riesling, with leaf size ranging from small to medium–large, showed highly above-average performance under sheep grazing. Synthetic lines 15 and 45 also had highly above-average performance under sheep grazing. Cvv. Legacy and Kopu II showed above-average performance under cattle and dairy grazing. Synthetics 15, 48, 49, 44, 22 and 18 and cv. Quartz had above-average performance under all three grazing managements. Synthetics 27, 33 and 38 had highly above-average performance across all three grazing managements and were superior to all 14 cultivars evaluated. Several of these superior synthetics are being tested across multiple grazing environments. Among the 14 cultivars evaluated, Legacy and Quartz showed superior seasonal growth performance across the three grazing managements. Quartz is being evaluated in several on-farm trials across temperate regions of the world.


1977 ◽  
Vol 24 (3) ◽  
pp. 307-321 ◽  
Author(s):  
J. F. D. Greenhalgh ◽  
F. W. H. Elsley ◽  
D. A. Grubb ◽  
A. L. Lightfoot ◽  
D. W. Saul ◽  
...  

SUMMARY1. Gestation diets formulated to contain A, 9; B, 11; C, 13 or D, 15% protein, and lactation diets with C, 13 or E, 17% protein provided eight treatment combinations. They were given at seven centres at 2 kg/day in gestation and approximately 5·7 kg/day in lactation to sows which remained on experiment for three to five parities and produced in total 468 litters. Mean results for parities one to four are given in this summary.2. For gestation diets A to D mean litter size at birth was 9·7, 10·1, 10·3 and 10·4 live pigs, and at weaning (at 6 weeks), 8·2, 8·7, 8·8 and 8·8. Sows which received lactation diets C and E subsequently produced 10·4 and 10·3 pigs at birth and 8·9 and 8·3 at weaning.3. Gestation diets had no consistent effects on piglet weights. During lactation, however, diet E gave heavier pigs than C, by 0·2 kg at 3 weeks and 0·5 kg at weaning.4. Extra protein for either gestation or lactation had a positive effect on sow weight at that stage, but a negative effect in the following stage. There were no direct treatment effects on the time required for re-conception.5. Twenty experimental sows at the Rowett Institute, together with an additional group given diet A for both gestation and lactation, showed strong positive relationships between lactation protein intake and milk yield or composition.6. The treatment combination AC (i.e. 9% protein in gestation and 13% in lactation) gave the lowest weight of weaned pigs per litter, and CC gave the highest. The remaining treatments gave similar weights; of these BC (nominally 11 with 13, but actually 11·5 with 13·5% protein) was concluded to provide the lowest protein intake consistent with satisfactory performance.


1980 ◽  
Vol 94 (2) ◽  
pp. 443-453 ◽  
Author(s):  
D. Wilman ◽  
A. A. Mohamed

SummaryThe regrowth of Aberystwyth S. 23 perennial ryegrass, S. 24 perennial ryegrass, S. 59 red fescue and S. 170 tall fescue was studied in field swards, comparing four levels of applied nitrogen, for 8 weeks following a clearing cut. The clearing cuts were in mid-October, mid-February and mid-March in each of 3 years, different plots being used on each occasion.The application of N increased the number of leaf primordia, the number of un-emerged leaves, the rate of leaf emergence and death, leaf blade length, width and weight, sheath length, number of leaves per unit area of ground and proportion of green tissue in total yield. The application of N had little effect on the number of leaves per tiller and tended to reduce weight per unit area of leaf blade. The increase in size, weight and number of leaf blades appeared to be major reasons for the positive effect of applied N on yield, previously reported; and the increase in sheath length contributed to the increase in proportion of yield above 4 cm. Rate of leaf extension was not closely related to yield and was more sensitive to temperature than was yield. Changes during regrowth in blade and sheath length helped to explain changes in weight per tiller, previously reported. The effects of improving weather conditions in late winter/early spring were similar to the effects of applied N: larger, heavier leaf blades, longer sheaths, a taller canopy, a lower proportion of dead material, younger leaves. The length of shoot apex per leaf primordium was relatively constant. Leaves continued to emerge, at a slow rate, in the period December–February. S. 170 had the biggest leaves, particularly in May, and the slowest rate of leaf turnover. Rate of leaf extension was increased by applied N more, on average, in the ryegrasses than in the fescues.


1959 ◽  
Vol 10 (4) ◽  
pp. 500 ◽  
Author(s):  
K Spencer

Plants of white clover (Trifolium repens L. var. Ladino) were grown in sand culture with four levels of sulphur supply. Growth increased with increasing sulphur supply, all plants except those at the highest sulphur level showing deficiency symptoms. As the severity of the deficiency increased, the root system formed a proportionately larger part of the plant, and the stems and petioles smaller proportions; the proportion of the whole plant formed by the laminae was reduced to only a slight extent. Nitrogen and sulphur fractions were examined in the laminae, nitrogen at each of three harvests and sulphur at the second harvest. The percentages of protein nitrogen and of total nitrogen increased as sulphur supply increased, protein nitrogen forming a greater proportion of the total nitrogen at the higher sulphur levels. In contrast, protein sulphur formed the bulk of the total sulphur in deficient plants, but as sulphur supply approached an adequate level for growth, there was a marked increase in non-protein organic sulphur and a smaller increase in sulphate sulphur. In this respect, white clover appears to differ from legumes other than Trifolium spp. and from non-legumes, all of which accumulate sulphur mainly as sulphate.


1999 ◽  
Vol 79 (2) ◽  
pp. 231-238
Author(s):  
R. Drapeau

Orchardgrass (Dactylis glomerata L.) has good winter survival in the mid-north agricultural areas of eastern Canada. There is no information on the cutting management to use after the first harvest of orchardgrass under these climatic conditions. The objective of this study was to determine the required interval between harvests following a first harvest at heading stage to optimise the productivity and maintain the persistence of orchardgrass. An interval of 35 d between harvests was sufficient to obtain annual yields of 4 to 6 tonnes of dry matter per hectare. An interval of 28 d between harvests had no negative effects on orchardgrass persistence under our climatic conditions. A second harvest taken 42 d after the first one often had a negative effect on the dry matter yield of the third harvest. Each time this occurred, we observed that the second harvest had been taken after 20 July. Heading dates varied among years. In addition to the growth stage at the first harvest, the date of occurrence of the heading stage should be considered so that the second harvest will be taken before 20 July. Consequently, if heading is delayed in spring, the interval between the first and second harvest must be reduced to take the second harvest before 20 July. Delaying the third harvest had a negative effect on the dry matter yield of the first harvest of the following production year. These results indicate that it is possible to take three harvests before September under the climatic conditions of the mid-north of eastern Canada without affecting the persistence of orchardgrass. Key words: Dactylis glomerata L., orchardgrass, cutting stage, cutting intervals, cutting management, yield


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